1. Technical Field of the Invention
The present invention relates to novel composite core/sheath particulates based on organic polymers and calcium carbonate, to hollow calcium carbonate particles or beads prepared therefrom and to liquid suspensions of such particulates and hollow CaCo.sub.3 beads.
This invention also relates to processes for the preparation of the subject novel particles and suspensions thereof and to the use of same as fillers or additives in plastics and elastomers.
2. Description of the Prior Art
Calcium carbonate is known to impart good rigidity to thermoplastic substrates by formulating particles thereof, having a particle size on the micron order, into the plastic. The latter then exhibits certain improved physical properties.
However, it too is known that plastics reinforced with calcium carbonate become much more brittle and their impact strength is weakened.
Further, inorganic fillers comprising particles of silica or carbon black have been formulated into elastomers and, in particular, into elastomers used for the manufacture of vehicle tires, to improve the tear and abrasion resistance of the elastomers. In turn, however, these reinforced tires lack flexibility at low temperature.